TMON: A Linux Kernel Thermal Monitor/Tuner

The latest open-source work being done for improving Linux thermal monitoring and tuning is the TMON project that hopes to be mainlined within the Linux kernel.

TMON is a kernel tool for monitoring and tuning the kernel's thermal subsystem. In announcing the latest work on the tool, its creator Jacob Pan describes the work as:

Increasingly, Linux is running on thermally constrained devices. The simple thermal relationship between processor and fan has become past for modern computers.

As hardware vendors cope with the thermal constraints on their products, more sensors are added, new cooling capabilities are introduced. The complexity of the thermal relationship can grow exponentially among cooling devices, zones, sensors, and trip points. They can also change dynamically.

To expose such relationship to the userspace, Linux generic thermal layer introduced sysfs entry at /sys/class/thermal with a matrix of symbolic links, trip point bindings, and device instances. To traverse such matrix by hand is not a trivial task. Testing is also difficult in that thermal conditions are often exception cases that hard to reach in normal operations.

TMON is conceived as a tool to help visualize, tune, and test the complex thermal subsystem.

Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via Twitter and Google+ or contacted via MichaelLarabel.com.